CHICAGO — Former House speaker Dennis Hastert, who less than a decade ago stood second in line to the presidency, was sentenced to 15 months in federal prison Wednesday for a bank fraud case linked to allegations he sexually abused teen boys more than 30 years ago.

Federal Judge Thomas Durkin called Hastert, 74, a “serial child molester” and rejected a prosecutor’s recommendation of six months in prison on a banking charge that carries a maximum five-year sentence. The court also fined Hastert $250,000 and sentenced him to two years of supervised release after leaving prison. Hastert must register as a sex offender.

“Nothing is more disturbing than having ‘serial child molester’ and ‘Speaker of the House’ in the same sentence,” Durkin said.

Hastert, who entered court in a wheelchair and needed help standing to address the judge, admitted for the first time mistreating some athletes when he was a high school wrestling coach in Illinois before he began his political career.